const mongoose = require("mongoose");
module.exports = new Promise((resolve,reject)=>{
    mongoose.set("useCreateIndex",true);
    mongoose.connect("mongodb://localhost:27017/styling_hair",{
        useNewUrlParser: true,
        useUnifiedTopology: true
    });
    mongoose.connection.once("open",err=>{
        if(!err){
            console.log("数据库连接成功");
            resolve();
        } else {
            console.log(err);
            reject(err);
        }
    })
})